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Updated: Jun 4, 2026
09:20
Laser Capture Microdissection of Mouse Embryonic Cartilage and Bone for Gene Expression Analysis
Published on: December 18, 2019
COL1 C-propeptide cleavage site mutations cause high bone mass osteogenesis imperfecta
Katarina Lindahl1, Aileen M Barnes, Nadja Fratzl-Zelman
1Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
Human Mutation
|February 24, 2011
Summary
Mutations in type I procollagen genes cause Osteogenesis Imperfecta (OI). Novel mutations disrupting collagen processing lead to a new high bone mineral density OI phenotype.
Area of Science:
- Biochemistry
- Genetics
- Orthopedics
Background:
- Osteogenesis Imperfecta (OI) is primarily caused by mutations in type I procollagen genes (COL1A1/COL1A2).
- Collagen maturation involves critical processing steps, including C-propeptide cleavage, essential for bone integrity.
Observation:
- Two children with mild OI presented with substitutions at the type I procollagen C-propeptide cleavage site.
- These mutations disrupted collagen processing, leading to a novel OI phenotype.
- Despite radiographic osteopenia, patients exhibited high bone mineral density (BMD) and increased mineralization.
Findings:
- Mutations in COL1A1 (p.Asp1219Asn) and COL1A2 (p.Ala1119Thr) impaired procollagen processing.
- FTIR imaging revealed elevated mineral/matrix ratios and increased collagen maturation in trabecular bone.
- Bone mineralization density distribution showed a shift towards increased mineralization, with one patient exceeding classical OI levels.
Implications:
- These findings define a new high-BMD OI phenotype.
- Procollagen C-propeptide cleavage is demonstrated to be crucial for normal bone mineralization.
- Understanding this pathway offers new insights into OI pathogenesis and potential therapeutic targets.
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